Return bend assembly



Oct. 6, 1936. M. P. YOUKER RETURN BEND ASSEMBLY Filed Aug. 28, 193sSECTION 7-7. FIG-7 INVENTOR.

I) SECTION 3-3 SGTION 6- Fl c-6 SEcTaoN5-5 A TTORNEY.

Patented Oct. 6, 1936 PATENT QFFICE RETURN BEND ASSEMBLY Malcolm P.Youker, Bartlesville, Okla assignor to Phillips Petroleum Company,Bartlesville Okla, a corporation of Delaware Application August 28,1933, Serial No. 587,205

2 Claims. (01. 285-420) This invention relates to improvements in areturn bend assembly to be used for connecting tubes in a tubular oilheater or the like.

The improvements which are disclosed in this present application forpatent are improvements in a return bend assembly which was originallydisclosed in the patent issued to the present applicant on June 28, 1932under United States Patent Ofiice Patent No. 1,864,879.

One of the objects of the invention is to provide a return bend assemblywhich may be readily dismantled or assembled for cleaning, replacementor repair of either the return bend itself or the tubes which are joinedby said return bend.

Another object is to furnish a return bend which may be used under highpressure with a maximum degree of safety and a minimum possibility oileakage.

With the foregoing objects outlined and with other objects in View whichwill appear as the description proceeds, the invention consists in thenovel features hereinafter described in detail, illustrated in theaccompanying drawing, and more particularly pointed out in the appendedclaims.

In the drawing Figure 1 is a side elevation of the entire return bendassembly connected to the extremities of two tubes.

Figure 2 is an end elevation of the return bend assembly.

Figure 3 is a cross section and elevation taken at 3-4 through Figure 1.

Figure 4 is a cross section of Figure 1 taken through 4-4.

Figure 5 is a cross section and elevation taken through Figure 1 at 5-5.

Figure 6 is a cross section and elevation through Figure l at t6.

Figure 7 is a cross section and elevation taken through Figure 1 atl--l.

Figure 8 is an enlarged cross section through the extremities of thetube and return bend on the vertical plane 6-6 of Figure 1.

Figure 9 is an enlarged cross section along vertical plane 'i'--lillustrating the bolted connection between a tie-plate and a flangewhich taken are parts of the assembly.

Referring to the drawingl designates tubes such as are employed intubular oil heaters. In accordance with the present invention, each endof such a tube is externally threaded as shown in Figure 6 for some'tion of the return bend d.

distance from its extremity, and on this threaded portion a flange 3 isarranged. The flange has internal threads so that it may be screwed upon the tube to such an extent that the threaded extremity of the tubewill be approximately flush with the face of the-flange.

A return bend it to which are rigidly attached bolt tubes 5 is rigidlyheld by bolts 6 in such position that the extremities of the return bend4 contact the extremities of the tubes 6. Bolts 6 are threaded intoflanges 3, extend through tubes 5, and the return bend 4 is drawn towardthe tubes 5 by means of tightening nuts l. Each extremity of the returnbend 4 is formed in the shape of a portion of the surface of a sphere,the center of which would lie approximately on the center lines of thetube i extended in the direc- The extremities of the tubes 1 which arebrought into contact with the ball face of the extremities of the returnbend 4 are formed in the shape of a spherical seat to receive the bailface of the return bend extremities. The radius of said spherical seatis preferably slightly longer than the radius of the spherical surfaceof the return bend ex- I tremity.

A tie plate 8 is attached by means of bolts 9 to the faces of flanges 3which are adjacent to the return bend 4. The bolts 9, which have conicalheads, pierce tie plate 8 through holes which are larger than the shanksof the bolts 9 and are tapped into flanges 3. When the bolts 9arescrewed into the iianges 3 the conical heads of the bolts 9 will holdthe plates 8 tightly against the flanges 3 without having to be threadedthrough the plates 8 and therefore will facilitate I dis-assembling thefittings.

It is apparent that after one of the'fianges 3 has been assembled oneach of the two tubes i, these flanges may be readily properlypositioned by means of attaching tie plate 8 to said flanges by bolts 9for the attachment of return bend by means of the bolt t and the nut'11.

While I have shown a convex spherical face on the extremity of thereturn bend and a concave spherical face in the extremity of the tube toreceive said convex spherical face, it should be understood that theconvex spherical face may be formed on the extremity of the tube and theconcave spherical face formed in the extremity of the return bend. As amatter of fact I have successfully used the latter combination offacings, as well as the former, with success. It should also beunderstood that in either case the concave face may be formed in theshape of the surface of a cone or in any other shape such that theconvex spherical surface will make a complete circular line contact withthe concave seat. It should also be understood that a gasket of suitablematerial may be used between these two contacting surfaces. It should benoted that due to the impossibility of maintaining alignment between thetubes it is necessary,

in order to successfully utilize this return bend assembly, that eitherthe extremity of the tube or the contacting extremity of the return bendmust be shaped in the form of a portion of the surface of a sphere.

In order that the return bend may conveniently be dismantled it isdesirable that all of the tubes 5 be extended to the same length.

While I have described in diagrammatic detail a form of my return bendassembly improvements, I do not propose to be limited by these exactdetails but propose to claim all of the advantages which are inherent inthese improvements. It should be particularly noted that the return bendmay be removed from the tubes without disturbing their position and thatlikewise any single part of the assembly. including the tubesthemselves, may be easily removed and replaced.

I claim:

1. A return bend assembly including a plurality of tubes, flangesconnected to the ends of said tubes, a link. joining the ends of saidtubes,

' a return bend connecting the ends of said tubes,

parti-spherical surfaces on the ends of said return bend contactingcomplementary surfaces on said tube ends, means for drawing said returnbend toward said tube ends and means independent of said aforementionedmeans for holding said links against said flanges.

2. A return bend assembly including a plurality of tubes, flangesconnected to the ends of said tubes, a link joining the ends of saidtubes, the tube ends projecting through said flanges, a return bendconnecting the ends of said tubes, parti-spherical surfaces on the endsof said return bend contacting complementary surfaces on said tube ends,means for drawing said return bend toward said tube ends and meansindependent of said aforementioned means for MALCOLM P. YOUKER.

